fix(storage): add missing options for PatchObject()

[coryan]

After all these years, we were missing some options for
storage::Client::PatchObject(). They were in the documentation, but
trying to use them would have resulted in a compilation error.

Part of the work for #4195

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This change is 

[google-cloud-cpp-bot]

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[codecov]

Codecov Report

Merging #8137 (a7efd6c) into main (950c774) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main    #8137   +/-   ##
=======================================
  Coverage   94.58%   94.58%           
=======================================
  Files        1320     1320           
  Lines      117813   117827   +14     
=======================================
+ Hits       111433   111451   +18     
+ Misses       6380     6376    -4     

Impacted Files	Coverage Δ
google/cloud/storage/client.h	99.79% <ø> (ø)
google/cloud/storage/internal/object_requests.h	97.10% <ø> (ø)
...gle/cloud/storage/internal/object_requests_test.cc	100.00% <100.00%> (ø)
...torage/tests/object_basic_crud_integration_test.cc	80.48% <100.00%> (+0.11%)	⬆️
google/cloud/pubsub/samples/samples.cc	92.33% <0.00%> (+0.23%)	⬆️
...le/cloud/internal/default_completion_queue_impl.cc	97.72% <0.00%> (+0.56%)	⬆️

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